Wet oxidation system

ABSTRACT

Process and apparatus for the oxidation of an aqueous suspension of organic matter at elevated temperature and pressure is disclosed. The organic matter is oxidized in a reactor having a reaction zone consisting of static mixer vane arrangement. The oxidized matter and oxygen-containing gas are circulated through the static mixer to promote the oxidation of the organic matter in reducing COD to the desired level.

This is a division of application Ser. No. 595,821, filed Apr. 2, 1984,U.S. Pat. No. 4,604,212.

FIELD OF THE INVENTION

This invention relates to process and apparatus for the wet oxidation oforganic matter using oxygen-containing gases such as air.

BACKGROUND OF THE INVENTION

Destructive oxidation of organic materials in an aqueous medium has beenemployed because it provides a useful process for reducing the chemicaloxygen demand of organics in water systems. This avoids the need tode-water the system in order to burn in a fuel system the organics.British patent No. 706,686 discloses a self-sustaining process for thedestructive oxidation of organic materials in an aqueous medium. Thesystem operates at a temperature above 450° F. and a pressure sufficientto maintain the water in liquid form so as to cause the organic materialto be oxidized. Such pressures may be in the range of 1400 to 1500pounds per square inch and the temperatures may be as high as 625° F.

Catalysts have been used in the system to catalyze the oxidationreaction, such as disclosed in U.S. Pat No. 2,690,425. The system isoperated at temperatures in the range of 100° C. to 350° C. underpressures of between 400 to 2500 pounds per square inch.

The reactor design for the wet oxidation system has been provided inmany forms, such as disclosed in U.S. Pat. No. 3,870,631. The reactor ishorizontally oriented and has several compartments to provide a seriesreactor arrangement. Agitators are used to provide a rubbing or abrasivecontact between the combustible organic matter and the oxygen over amaximum area by reason of the high state of movement during agitation bythe agitators. The agitators are power intensive in view of the speedsat which they must rotate to generate the degree of agitation requiredin the wet oxidation process of that patent, e.g. they may be rotated atspeeds of 1300 rpm.

Another approach in agitating a liquid system is to use ultrasonicenergy as disclosed in U.S. Pat. No. 4,013,552. Ultrasonic energy istransmitted to sewage which is at standard temperature and pressure.This treatment reduces the liquid particle size and enrobes the reducedwater particles with air to enhance the biochemical oxidation by theaerobic bacteria. However, this patent does not contemplate the use ofultrasonic energy in the chemical oxidation of organic matter. AlthoughU.S. Pat. No. 4,003,832 discloses the use of ultrasonic energy inchemical oxidation of organic matter, this patent requires the use oflarge concentrations of ozone in the area of the ultrasonic energygenerator.

U.S. Pat. No. 4,155,848 discloses a vertical reactor tower for use inthe wet oxidation of organic matter. The vertical tower has an outercyclindrical vessel with a smaller diameter concentric tube therein. Theintroduced organic matter and oxygen are circulated downwardly of theannular portion of the vessel and upwardly of the interior of thereactor core. The oxygen is introduced into the base of the inner tubeso that in flowing upwardly, it causes a circulation of the aqueousmedium in the system. This requires considerably increased supply ofcompressed air to cause the necessary circulation. The process,therefore, become cost ineffective because of the high capital andenergy intensive system needed to compress this air. The system isnormally operated at temperatures in the range of 250° C. to 374° C. Thepressure is high enough to maintain the effluent in liquid phase.

SUMMARY OF THE INVENTION

According to an aspect of the invention, the process for oxidizing anaqueous suspension of organic matter in reducing the chemical oxygendemand of the organic matter to a predetermined level is carried out atan elevated temperature and pressure by exposing the organic matter toan oxygen containing gas for a sufficient period of time.

The process is carried out in a reactor having a reaction zoneconsisting of a static mixer vane arrangement and means for circulatingthe aqueous suspension of organic matter through the static mixer vanearrangement. The process comprises operating the reactor at the elevatedtemperature and pressure which promotes the oxidation in the aqueousmedium of organic matter with minimal generation of steam. An oxygencontaining gas is introduced into the aqueous suspension of organicmatter. The aqueous suspension of organic matter and bubbles of oxygencontaining gas are split, rearranged and combined in the static mixer asthey are circulated through the static mixer by the circulating means toreact the organic matter with the oxygen. The treated organic matter iswithdrawn from the reactor reducing the chemical oxygen demand to thepredetermined desired level.

According to another aspect of the invention, the apparatus having thereaction zone consists of the static mixer vane arrangement with themeans for circulating the aqueous suspension of organic matter throughthe static mixer vane arrangement. Means is provided for introducing anoxygen containing gas into the reactor and means for introducing anaqueous suspension of organic matter into an area of the reactorseparate from where the oxygen containing is introduced. The staticmixer comprises a plurality of vanes arranged within the reaction zoneto split, rearrange and combine the aqueous suspension of organic matterand oxygen containing gas bubbles. Means is provided for withdrawingtreated organic matter in aqueous suspension and gases from the reactor.

According to another aspect of the invention, ultrasonic energy wavesmay be used in the reactor to further enhance the oxidation reaction bybreaking up already partly oxidized organic matter. In addition, thestatic mixer vanes may have at least portions thereof coated with acatalyst for the oxidation reaction.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are shown in the drawingswherein:

FIG. 1 is a schematic view of the reactor and heat exchanger for use inthe wet oxidation of organic matter and in which the process, accordingto this invention, is carried out;

FIG. 2 is a schematic view of an alternative embodiment of the reactorhaving a plurality of reaction zones defined therein in which theprocess, according to this invention, is carried out; and

FIG. 3 is a section along lines 3--3 of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The process and apparatus, according to this invention, is useful inmost wet oxidation applications such as in the disposal of sewage,slime, sludges and other organic waste including organic plastics andexplosives. The oxidative combustion is controlled, as carried out underwater, where the pressure is sufficient to minimize the production ofsteam during the reaction. By use of the static mixer vane arrangementin the reactor core, the overall reactor configuration is considerablysimplified compared to the power intensive type such as disclosed inU.S. Pat. No. 3,870,631.

Considering the process as carried out in a preferred embodiment for theapparatus of FIG. 1, a vertically oriented reactor 10 comprises an outercylindrical pressure vessel 12 with closed upper and bottom end portions14 and 16. According to this construction, the upper end 14 comprises anouter plate 18 bolted to an annular ring 20 which is welded to the outerpressrre vessel 12. Sealing material 22 is used in sealingly engagingthe outer plate 18 to the annular ring 20. An ultrasonic probe 24extends through the plate 14 and is sealingly engaged with the gasketmaterial 22 as it extends into the reactor 10.

The bottom 16 is similarly sealed with an outer plate 26 bolted to anannular ring 28 which is welded to the outer vessel 12. A gasket 30 isused in sealingly engaging the outer plate 26 with the vessel 12. Abearing and sealing arrangement 32 is provided for the drive shaft 34which drives the vanes 36 of the pump unit 38 which, according to thisembodiment, is located at the bottom portion of the reactor 10. Theseals and bearing arrangement 32 is such to withstand the temperaturesand pressures at which the reactor 10 operates. A pulley 40 is providedon the drive shaft which is connected by way of appropriate V-belt to adrive motor. The reactor 10 includes, interior and concentric with thecyclindrical outer pressure vessel 12, an inner tube 42. The inner tubeis shorter than the outer vessel 12 to define an upper space 44 and alower space 46, thereby providing communication between the reactor core48 defined in the interior of the inner tube 42 and the outer annularreactor chamber 50 which surrounds the reactor core.

The circulating pump 38 is located in the lower region 46 with the vanes36 extending upwardly into the interior portion 52 of the inner tube 42.The vanes are so configured to circulate the aqueous suspension in gasesupwardly of the inner core in the direction of arrows 54. As thesuspendion and gases emerge from the upper region 56 of the reactor,they flow over the rear portion 58 of the inner tube in the direction ofarrow 60, thus flowing downwardly for recirculation upwardly of theinner core in the direction of arrow 54.

On start-up of the reactor 10, it is heated to the operatingtemperatures and pressurized to the operating pressures. In order totreat common industrial wastes, the operating temperatures are normallyin the range of 200° C. to 230° C. and pressures in the range of 35 to45 kg/cm². However in treating waste from oil recovery systems tothereby generate energy, the systems may operate at pressures in therange of 210 kg/cm² and temperatures in the range of 320° C. in treatingwaste from heavy oil and tar sands bitumen recovery systems. The outervessel 12 is reinforced and made of a material which can withstand theoperating pressures and temperatures with added safety margin. Normallythe reactor 10 is elevated to the operating temperature by purging thesystem with live steam and then pressurized as the high pressure aqueouswaste stream and oxygen-containing gas are introduced to the reactor.heat exchanger 62 is used to heat exchange the hot treated waste liquidand gases with incoming waste materials and the oxygen-containing gaswhich may be air. The waste to be treated is introduced to the heatexchanger 62 via line 64. The air is introduced to the heat exchangervia line 66 which flows upwardly of the heat exchanger. The heated wastestream emerges from the heat exchanger in line 68 and is introduced tothe outer reactor chamber 50 via inlet 70 at the rear of the reactor 10.The inlet 70 has a nozzle portion which directs the introduction of thewaste stream circumferentially of the annular chamber 50 so that theaqueous suspension circulates downwardly of the outer chamber 50 in aspiral manner.

The heated air exits the heat exchanger in line 72 and is introduced atthe first location by inlet 74 for mixing with the dwwnwardly travellingaqueous suspension. Optionally, there may be a second inlet 76 forintroducing additional fresh oxygen-containing gas to the outer chamber50 further downstream of the inlet 74.

The treated waste liquid and gases are removed from the upper region 44of the reactor via outlet 78 which passes the treated liquid and gasesdownwardly of the heat exchanger via line 80. The hot waste liquid andgases are heat exchanged with the incoming untreated waste stream andair. As the waste liquid and gas is cooled, the gases separate and exitfrom the heat exchanger via line 82. The condensed liquids emerge fromthe heat exchanger via line 84.

The reactor core 48 includes a static mixer vane arrangement 86 which issecured and remains stationary within the inner tube 42. The circulatingpump 38 circulates upwardly the aqueous suspension and gases over thevanes 88 and 90 of the static mixer. The vanes are shaped and configuredas shown by the different arrangements of 88 and 90 to split, rearrangeand combine the stream. The flow rates upwardly of the reactor core aresuch that the organic matter and bubbles of oxygen-containing gas, whichmay be air, are subdivided so as to expose fresh surfaces of the organicmaiter to oxygen and further oxidize the organic compounds. The staticmixer vane arrangement extends from the lower region of the inner tubeupwardly of a majority of the inner tube. Above the static mixer is theupper region 92 which is left vacant.

According to a preferred embodiment of the invention, an ultrasonicprobe 24 is located in the upper region 92. By way of the ultrasonicenergy, the already oxidized particles of organic matter are furtherbroken up to expose fresh surfaces which are oxidized by the bubbles ofair. The air bubbles may be imploded by the ultrasonic energy to exposemore oxygen to the fresh organic surfaces in enhancing the oxidation ofthe organic matter.

The upper end of the inner tube is sloped to provide a lowermost portionwhich defines the weir 58. Thus the treated materials flow over the weirin a direction away from the outlet 78 to enhance the circulation of thematerials. The liquid level in the reactor may be slightly above theoutlet 78 so that the treated organic matter and entrained gases areremoved. Above the outlet, there is the upper space 44 where some gasesmay remain, but principally in all reaction zones within the outerchamber 50, the inner core along the static mixer and at the ultrasonicprobe, there are no vapour regions.

Thus the reactor 10 provides, according to this preferred embodiment,three reaction zones. A first reaction zone is provided in the outercore 50 where the introduced untreated organic matter is exposed tooxygen at inlets 74 and 76 for the incoming fresh air. The secondreaction zone is defined in the static mixer 86 along its length wherebyadditional splitting and refolding of the materials, further oxidationof the organic matter takes place. The third reaction zone is in theregion of the ultrasonic probe 24 which breaks up the remaining oxidizedorganic matter, particularly the small organic molecules, to furtheroxidize the materials to the extent in forming carbon dioxide and carbonmonoxide. It has been found that produced acetic acid, which is mostdifficult to break down in other types of prior wet oxidation systems,can be broken down by this system.

Violent agitation of the system is avoided in each of the reactionzones. The circulating pump 38 merely circulates the fluid downwardly ofthe outer annular reactor chamber 50 and upwardly over the static mixervanes 86. There is no violent agitation in the area of the pump 38 andthe air, as introduced, is at spaces remote from the vanes of the pump38.

The static mixer may have a variety of vane configurations which arereadily available in the marketplace. For example, the "Statiflo"(trademark) motionless mixers as distributed by Statiflo Inc. provide anacceptable static mixer. Another example is the static mixer distributedby Koch Engineering Company Inc. Additional details of static mixers andtheir applications may be found in International Chemical Engineering,Volume 22, No. 2, April 1982, 197.

By use of the static mixer, the mixing of the components is accomplishedwith a minimum of power input, approximately one tenth of that requiredto operate the agitating devices of other units and achieve adequatemixing to oxidize extensively the materials.

The use of a motionless mixer providing extended surface area along itslength lends itself readily to the use of catalysts for the oxidationreaction. The surface of the vanes of the static mixer can be formed ofor include catalysts which, at these temperatures and pressure, catalyzethe oxidation reaction. Suitable catalysts are metallic oxides ofcopper, nickel, cobalt, chromium, manganese, platinum, palladium, iron,cerium or silver. Mixtures of such oxides are useful, such as copperoxide/zinc oxide (50:50), copper oxide/chromium oxide/magnesium chromate(1:1:.004 by weight) and nickel oxide/nickel chromate (50:50). Othercatalysts include magnesium sulphate and ammonium vanadate. Anothercatalyst mixture includes manganese, chromium/zinc (80/47/20).

The dimensions of the inner tube and the outer vessel are selected suchthat with the particular circulation rate of the pump 38, the flow ofthe aqueous suspension downwardly of the outer annular chamber isincreased relative to the upward flow through the static mixer. Thisincreased flow down the outer reaction chamber ensures that theoxygen-containing gas, as introduced at points 74 and 76, is entrainedin the suspension and moves downwardly with the aqueous suspension so asto be present in the suspension when travelling upwardly through thestatic mixer.

According to a preferred embodiment of the invention in treating normalorganic industrial waste, the dimensions of the inner tube to the outertube provides volume ratios in the range of 2:1.

Because of the unique reactor design, there is considerably lowercapital costs in equipment as compared to other arrangements, higheryields are realized in chemical oxygen demand reduction compared toother reactor designs. The arrangement, according to this invention,involves fewer valves and control equipment. The modular approach to thereactor provides for multiples thereof in providing series reactors. Inarranging for a series of reactors, the treated waste liquid and gas inline 80 would be introduced to a downstream reactor corresponding toreactor 10 at inlet 70. Air would be introduced to the downstreamreactor again at point 74 and 76. A plurality of reactors may be soarranged where the treated waste liquid from each reactor is transferredto the next. The treated waste liquid and gas removed from the lastreactor in the series would then be returned through the heat exchanger.Multiples of reactors may be used in the circumstances where extendedoxidation reactions are required to fully reduce the chemical oxygendemand in the introduced waste liquid.

The use of ultrasonic energy in association with a multiple reactorsystem provides additional benefits The use of the ultrasonic energy tobreak up the organic matter, as it emerges from the static mixer reactorzone, provides fresh surfaces for oxidation which when transferred tothe downstream reactor, is contacted with fresh oxygen containing gas toexpedite the oxidation of the broken up organic materials in thedownstream reactor. It is appreciated that a wide range of ultrasonicfrequencies may be used, such as from 10 kilohertz to 100 kilohertz.

The apparatus may be operated on either a batch or continuous basis. Fora batch basis, the reactor 10 is initially heated to the operatingtemperature by use of live steam which may be introduced via inlet 70and removed via outlet 78. Once the reactor is up to operatingtemperature, the aqueous suspension of organic matter is introduced viainlet 70 at the operating pressure until the predetermined batch volumeof aqueous suspension is introduced to the reactor. The heated air isintroduced at operating temperature and pressure via inlets 74 and 76 tocommence the oxidation of the organic matter. The air is continuouslyintroduced during the operation of the apparatus until the chemicaloxygen demand of the organic matter is reduced to a desired level. Atthat time, the reactor is purged of the treated material in preparationfor treating the next batch or shutdown.

When the reactor 10 is operated on a continuous basis, the aqueoussuspension of organic matter and oxygen-containing gas are introduced atrates which provide a residence time for the organic matter in thereactor to reduce the COD (chemical oxygen demand) to the desired level.The treated waste liquid and gases are continuously removed from outlet78 in the manner previously discussed.

The alternative embodiment for the reactor design is schematically shownin FIG. 2. The reactor 100 comprises an outer shell 102 only the lowersection of which is shown. In view of the prior discussion of thecomplete reactor of FIG. 1, the upper portion would be similar withrespect to the location of means for withdrawing treated organic matterfrom the upper region of the reactor along with location of anultrasonic probe above the reactor cores 104, 106 and 108 which arepositioned within the reactor shell 102 as shown in the section of FIG.3. The reactor tubes 104, 106 and 108 are very similar to the reactortube of FIG. 1. By providing a multiplicity of the reactor tubes in thereactor 100, variations on the circulation can be achieved employing apump which may be located either internally or externally of the reactor100. Each reactor tube 104, 106 and 108 has corresponding tubular wallportions 110, 112 and 114. A static mixer vane arrangement generallyindicated at 116 in tube 104 is located in each of the tubes to define acorresponding reaction zone. The aqueous suspension of organic matterand oxygen-containing gas are introduced to the reactor 100 in a mannersimilar to that with the reactor 10 of FIG. 1. The flow of the material,according to this embodiment, is upwardly of each of the reactor cores104, 106 and 108. By arranging the reactor cores contiguous one anotherand surrounded by the reactor shell 102, three discrete and independentchannels 118, 120 and 122 are provided. The material overflows thesetubes and flows downwardly of the reactor via the channels 118, 120 and122. This circulation is induced by pump 124 which removes thedownwardly flowing organic material in suspension via the respectiveoutlets 126, 128 and 130. The outlets, in communication with conduits132, 134 and 136, transfer the materials to the inlet side 138 of thepump 124. The pump 124 is driven by motor 140 connected by a drive shaft142. The pump has a single outlet 140 which is connected to a manifold142 consisting of a cage network 144 which divides the output of 140into three outlet portions 146, 148 and 150. The outlet portions extendinto the respective tubes as shown in FIG. 3. By circulating pump 124located exterior of the reactor 100, a circulation of the aqueoussuspension of organic mattrr and oxygen-containing gas is achievedwithout violent agitation at the base of the reactor 100. Depending uponwhether the reactor 100 is operated on a batch or continuous basis, theflows are prescribed so as to provide the necessary residence time ofthe organic matter in the reactor 100 to achieve the desired reduttionin chemical oxygen demand of the materials being treated.

As with the static mixer vane arrangement of the reactor of FIG. 1, thestatic mixer vane 116 in each reactor tube may be coated with suitablecatalysts for the oxidation reaction. An ultrasonic probe may be locatedabove the grouping of three reactor tubes in the upper region of thereactor or a probe provided for each of the tubes similar to the mannershown in FIG. 1. It is understood in keeping with the alternativeembodiment of FIG. 2 that many other configurations internally of thereactor may be provided to achieve a plurality of reaction zoneseffected by the static mixer vane arrangements.

The process of the invention has been carried out in the reactor designof FIG. 1 having two towers in series using a sugar water test streamhaving a 7% COD. The reactor system was operated on a continuous basiswith a reactant residence time of one hour. Samples of treated oxidizedstream were collected. The collected samples were analyzed to reveal atsteady state condition a COD reduction of 91%. With the ultrasonic probeactivated, a further 5% reduction of COD was achieved to realize anoverall COD reduction of 96% during steady condition. It is appreciatedthat the use of an appropriate catalyst of the type previously discussedwould further increase the overall percentage COD reduction.

The apparatus and process of this invention is capable of operating atthe reduced temperatures and pressures for a wet oxidation system ascompared to the substantially higher temperatures and pressures used inmany of the prior art systems. In veew of the unique aspects of thereactor, the system is considerably more economic and compared to somesystems will cost one third of the prior systems. By using the modularconcept for the reactors, larger volumes of waste material can beprocessed by simply adding more units to the system. The modules can beinventoried, thereby shortening delivery time. Heat exchange within thereactor is facilitated by the design of having an inner reactor coresurrounded by an outer reactor chamber. The downflow section of thereactor removes heat from the energy created in the upflowing materialof the central core. Thus less demand is placed on the heat exchanger inheating the waste materials to be introduced to the reactor. Thecirculation pump for use in circulating the aqueous medium requiresabout 10% of the power required to drive the agitators of the morecomplex, multi-chamber systems, such as disclosed in U.S. Pat. No.3,870,631.

Although preferred embodiments of the invention have been describedherein in detail, it will be understood by those skilled in the art thatvariations may be made thereto without departing from the spirit of theinvention or the scope of the appended claims.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:
 1. An apparatus in whichoxidation of an aqueous suspension of organic matter at elevatedtemperature and pressure is carried out by exposing organic matter to anoxygen-containing gas in a reactor for a period sufficient to reducechemical oxygen demand of the organic matter to a predetermined desiredlevel, said apparatus comprising a reaction zone consisting of a staticmixer vane arrangement and means for pumping and thereby circulatingsuch aqueous suspension of organic matter through said static mixer vanearrangement, means for introducing an oxygen-containing gas into saidreactor and means for introducing an aqueous suspension of organicmatter into an area of said reactor separate from where saidoxygen-containing gas is introduced, said static mixer comprising aplurality of vanes arranged within said reaction zone to split,rearrange and combine the aqueous suspension of organic matter andoxygen-containing gas bubbles as said aqueous suspension is pumped andthereby circulated about said vane arrangement and means for withdrawingtreated organic matter in aqueous suspension and gases from saidreactor.
 2. An apparatus of claim 1, wherein said reaction zone isdefined by a reactor containing said static mixer vane arrangement. 3.An apparatus of claim 2 wherein a plurality of said reactor cores areprovided within said reactor, said pumping means circulating saidaqueous suspension of organic matter through said reactor cores.
 4. Anapparatus of claim 3, wherein said reactor cores extend generallyparallel with one another within said reactor, a plurality of channelsbeing provided in said reactor, said pumping means returning saidaqueous suspension through said channels for recirculation through saidreactor cores.
 5. An apparatus of claim 4, wherein each of said reactorcores is a cylindrical tube containing said static mixer vanearrangement along its length, said plurality of reactor cores beingpositioned adajcent one another, said reactor cores, said channels beingdefined between said reactor cores and said raactor shell.
 6. Anapparatus of claim 5, wherein said reactor is vertically oriented, meansfor removing said returned aqueous suspension from the bottom of saidchannels and conducting said removed aqueous suspension to a pumpextension of said reactor, a manifold located at the base of saidplurality of reactor cores, said manifold comprising an inlet connectedto said pump and a plurality of outlets corresponding to the number ofreactor cores, said manifold outlets being positioned below therespective reactor cores, said pump circulating removing aqueoussuspension of organic matter and oxygen-containing gas bubbles upwardlyof said reactor core via said manifold.
 7. An apparatus of claim 5,wherein aaid reactor is vertically oriented, said pumping means beingpositioned beneath said reactor cores to circulate returned aqueoussuspension of organic material and oxygen-containing gas bubblesupwardly of said reactor cores.
 8. An apparatus in which oxidation of anaqueous suspension of organic matter at elevated temperature andpressure is carried out by exposing organic matter to anoxygen-containing gas in a reactor by means for pumping and therebycirculating for a period sufficient to reduce chemical oxygen demand ofthe organic matter to a predetermined desired level, said apparatuscomprising a reactor for vertical orientation and having an innercylindrical open-ended tube defining a cylindrical reactor core andouter concentric cylindrical tube spaced from said inner tube to definean outer annular reactor chamber surrounding said reactor core, saidinner tube being shorter than said outer tube to define upper and lowerregions of fluid communication between said reactor core and outerannular chamber, said outer tube having closed ends to define a sealedreactor where said outer tube is fabricated of materials and reinforcedto withstand pressures and temperatures in its operating range, meansfor introducing an aqueous suspension of organic matter into the upperregion of said outer annular reactor chamber and first means forintroducing an oxygen-containing gas spaced from said introdution meansfor the aqueous suspension, a circulation pump located in said lowerregion for circulating the aqueous suspension of organic matter andgases upwardly of said reactor core and downwardly of said outer annularreactor chamber, a static mixer vane arrangement provided in said innertube and extending from the lower region of said inner tube and along amajority of said inner tube, said static mixer comprising a plurality ofvanes arranged within the cylindrical reactor core to split, rearrangeand combine the aqueous suspension of organic matter andoxygen-containing gas bubbles as said aqueous suspension is pumped andthereby circulated upwardly over said vane arrangement and meansprovided for withdrawing treated organic matter in aqueous suspensionand gases from said upper region.
 9. An apparatus of claim 8, whereinmeans for generating ultrasonic energy waves is positioned within theupper region of said inner tube above said static mixer vanearrangement.
 10. An apparatus of claim 9, wherein said catalyst isselected from the group consisting of manganese/chromium/zinc, ammoniumvanadate, copper oxide, nickel oxide, cobalt oxide, chromium oxide,cerium oxide, silver oxide; copper oxide/zinc oxide, copperoxide/chromium oxide/magnesium chromate and nickel oxide/nickelchromate.
 11. An apparatus of claim 8, wherein at least portions of saidstatic mixer vanes an outer surface of a catalyst for oxidation reactionof organic matter with oxygen.
 12. An apparatus of claim 8, whereinsecond means is provided for introducing additional oxygen-containinggas into said outer reactor chamber below said first means and abovesaid lower region of the reactor.
 13. An apparatus of claim 8, whereinthe dimensional ratios of said inner tube to said outer tube providevolume ratios in the range of 2:1.
 14. An apparatus of claim 8, whereinthe upper end of said inner tube is adapted to induce emerging treatedaqueous suspension of organic matter and gases to flow away from saidwithdrawal means.
 15. An apparatus of claim 14, wherein the upper end ofsaid inner tube is sloped laterally downwardly in a direction away fromsaid withdrawal means, said withdrawal means being level with or belowthe lowermost portion of said sloped upper inner tube end, saidwithdrawal means being opposite said lowermost tube end portion wherebyflow of treated aqueous suspension of organic matter and gases isinduced to flow away from said withdrawal means.
 16. An apparatus ofclaim 8, wherein said withdrawal means includes means for transferringthe treated high temperature aqueous suspension for heat exchange withseparate streams of incoming untreated aqueous suspension of organicmatter and oxygen-containing gas to elevate said incoming materials tothe operating temperature of said reactor.
 17. An apparatus of claim 8,wherein said static mixer vanes are spaced above the lowermost portionof said inner tube to provide a space within said inner tube, said pumpbeing a centrifugal pump with vanes extending upwardly into said space.18. An apparatus of claim 8, wherein a plurality of said reactors areinterconnected in series, said withdrawal means including means fortransferring treated aqueous suspension of organic matter and gas tosaid first introduction means of the next downstream reactor, saidwithdrawal means of the last reactor of said series including means fortransferring the treated aqueous suspension of organic matter and gasesto a heat exchanger for heat exchange with incoming untreated aqueoussuspension of organic matter and oxygen-containing gases.